Eventos Anais de eventos
MECSOL 2022
8th International Symposium on Solid Mechanics
Aeroelastic Study of a Rotary-Wing using Non-linear Numerical Analysis
Submission Author:
André Florentino Ribeiro , MG
Co-Authors:
André Florentino Ribeiro, Carlos Pagani, Murilo Sartorato
Presenter: André Florentino Ribeiro
doi://10.26678/ABCM.MECSOL2022.MSL22-0200
Abstract
Rotary-wings aeroelasticity is a field widely studied in order to improve the accuracy of fluid-structure interaction responses using low computational effort. These aeroelastic analyses demand integrated models for both the structural and the aerodynamical theories to properly describe the behavior of a rotary-wing, especially when the wing is mainly made of composite material. However, some strategies can be used to facilitate how the numerical responses can be obtained. This work proposes the implementation of a semi-aeroelastic numerical model that uses a mixed variational finite element theory to analyze the aeroelastic behavior of a rotary-wing. The structural model, which predicts the internal stress and the external deformations, stems from the Variational Asymptotic Method (VAM) and relies on the Variation Beam Section Analysis (VABS) to be capable of modeling composite material structures as geometrically non-linear beams, since wings are high aspect ratio components. The method VAM proposes the representation of a three-dimensional analysis in two complimentary formulations: a cross sectional 2D analysis and a 1D length-wise analysis set at each cross-section. Also, the aerodynamic model, which computes the driving distributed loads on the structure, is a finite-state inflow based on the thin airfoil theory that predicts the rotor aerodynamic field. Although the aerodynamic model can compute the induced velocity of each wing element, this would require high computational performance, so the present work will import the induced velocity of the blade from a Blade Element Moment Theory (BEMT) analysis using an interaction process. For the purpose of assembling the distributed aerodynamic load in the finite element structural model, the distributed load will be transformed into concentrated equivalent loads in each element node using the numerical integration Gauss Quadrature Method. Furthermore, the Newton-Raphson Method is applied to numerically solve the non-linear equations for obtaining the steady-state response of a wing along the aerodynamic field in terms of geometric parameters, material properties, rotary speed and aerodinamic coefficients. This formulation will be used to describe the aeroelastic behavior of a rotary-wing mainly made of carbon-epoxy laminate and aramid fiber honeycomb composite materials that has the UH60A airfoil as cross-section, which is an airfoil applicable in the construction of helicopter rotor blades. The results involve obtaining the aerodynamical efforts, that is, the lift, drag forces and the torsional momentum, also the internal efforts and the linear and angular displacements. This procedure would give the aeroelastic behavior of the wing at low computational cost.
Keywords
Finite Element Method, fluid-structure interaction, Non-linear analysis, Aerospace engineering, Rotary Blades, Composite Materials
